Cut-off machine



Feb. 1s, 1936. Q W SW.F'T, JR 2,031,512

CUT-OFF MACHINE Filed July 2, 1955 2 Sheets-Sheet lo """q Ri IE m j G nx mi; 5

l wie i l d I WHA, I" nfl( n A l I y| A I n i g l i :l l g :g f 1 S 1 :1 z 'i C? @Q N QG b. N\\ O la d O`N "SE W 7 lNvENToR ATTORNEYS Feb. 18, 1936. Q w1 SwlFT, JR 2,031,512

CUT- OFF MACHINE Filed July 2, 1935 2 Sheets-snee*v 2 INVENTOR 20# 0, @wz/Jj. mi @J7 Hw? ATTORN EYS Patented Feb. 1s, 1.936

UNITED STATES PATENT ori-lcs CUT-OFF MACHINE Application July 2, 1935, Serial N0. 29,471

9 Claims.

In converting corrugated paper board into box blanks, and analogous operations, it is necessary to cut the webs or lengths of material-usually as delivered from some prior operation, into fr lengths which may vary over a comparatively wide range, and it is frequently required that the machine operate very precisely so as to avoid variations in length of cut, under a given setting. To avoid injury to the material being cut, or to the machine, it also may be required that the knife travel substantially in the same direction and at substantially the same speed as the material when cutting. Variousmechanisms have been proposed and used in an effort to satisfy the above requirements, some involving clutches and timing devices acting to throw the knives into and out of operation at predetermined (but adjustable) periods, and others involving variable speed transmissions of various types used in conjunction with adjustable differential gearings, gearings for imparting pulsating movements to the knives, etc. i

It has been generally characteristic of -such prior machines that they involved a large number-of complicated and expensive mechanisms, and the primary object of the present invention is to provide a machine by which the above mentioned combined requirements of ready adjustment to different lengths of cut, precision of cut,

eration, may be satisfactorily accomplished in a simpler and less cumbersome and expensive way.

Further objects and advantages of the invention will be in part obvious and in part specifically referred to in the description hereinafter contained which, taken in conjunction with the accompanying drawings, discloses a preferred embodiment of the invention. Such embodiment, however, is to be regarded as merely illustrative of the principles of the invention. In the drawings- Fig. 1 is a side view of a cut-off mechanism adapted to operate in accordance with the invention.

Fig. 2 is a view similar to Fig. 1, but with certain parts cut away, and illustrating a dierent form of mechanism for regulating the speed of the cutters. l In its broader aspects, the invention involves the use of a variable speed motor serving as al drive for the cut-cil? knives, lin lcombination with a mechanism operating in timed relation to the cut-off to so adjust the speed of the motor that i) it always keeps the knives moving substantially.

and avoidance of injury during the vcutting op.

at the speed of the material being cut during the cutting operation, but may be set to vary the time between cutting operations as desired and thus enable the length of cut to be varied as desired while maintaining proper cutting speed.

In order that the desired length of cut may be obtained with precision it is necessary that the motor be capable Aof exceedingly close and accurate regulation in speed, and I prefer to use for the purpose a rotary electric motor of the type 1 having field and armature windings associated Ain shunt relation, and provided with a control member tov shift the armature and eld structures axially one with respect to the other, whereby variations in output speed of the motor may be obtained. Motors of this type are not new per se, but in so far as I am aware the possibility has been neither suggested nor demonstrated of satisfying the above mentioned combined requirements of a cut-off mechanism-or other rotary tool operating upon material progressively fed through the machine-by combining such a motor and its control member with a mechanism operating periodically in timed relation as above mentioned to cut selected lengths as desired, and maintain proper cutting speed in all settings.

'I'he invention is illustrated as applied to control the movement of a pair of cut-off knives l and 2; these and the associated parts employed to support and drive them are not described in great detail herein, since many knife constructions having a component of movement in the direction of feed of the materialr to be cut, at the time of cutting, and capable of being used for i present purposes, are well known in the art. In the illustrated form the knives I and 2 are carried respectively by parallel rotary shafts 3 and 4 supported in suitable side frames 5 mounted upon a suitable bed 6, and the shafts 3 and 4 are 40 connected by gears 1 and 8, so that as the shafts rotate, the knives I and 2 come periodically into conjunction to operate on the material between them. The material will be fed to the knives at a controlled rate by suitable mechanism (such as rolls la) well known in the art, and with a given rate of feed, it will be understood that the length of cut depends upon the frequency at which the knife or knives come into operating position. It will also be understood that unless special control be provided for the speed of the knives, with the material to be cut traveling at a given rate, alterations in the length of cut will cause the knives to travel at different speeds when in operating position,- which may be greater or less than the rate of travel of the material being cut. If the knives travel materially faster than such material when cutting, tearing or other injury to the material or mechanism may result, and likewise if the knives travel at a substantially slower speed when cutting, buckling of the material or injury to the mechanism may likewise result. 'Ihe present embodiment of the invention is designed primarily for cutting corrugated paper board as continuously delivered from the making machine, into blanks of desired length, but analogous problems may be met with in the case of other tools traveling at the time of their operation in the direction of material to be 0perated upon which is being fed past them, and reference to cut-off mechanisms in the present specification and claims accordingly should be understood as embracing other tools or operating members for performing printing, cutting, creasing, impressing, or like operations upon progressively traveling material and presenting analogous problems as above described, within the scope permitted by the prior art. In order to control the motion of the cut-01T knives with the above objects in view, I prefer to employ a variable electric motor 9 having an output shaft I 0; this motor as above stated is preferably of a type which was previously known, and accordingly will not be described in detail herein. It may be regarded in a general way as conforming to the patent to Lincoln No. 847,088, March 12, 1907, the shaft I0 corresponding to the shaft e of the aforesaid patent, and the motor 9 being provided with a speed control member II which may be regarded as conforming in a general way to the member o of the aforesaid patent. By adjustment of the position of control member II, the armature of the motor 9 is shifted axially with respect to its field to vary the rotary speed of output shaft I0, all as is shown and described in greater detail in said patent. Reference to said patent should be understood merely as indieating a type of motor suitable for present purposes.

Suitable driving connections are provided between the output shaft I0 of the motor and the 'cutoff knives; in the present instance a worm I2 is splined to shaft Il, and suitably held in position between bearings I3 and I I. This worm I2 driving a worm wheel I5 mounted on a shaft I.

The speed of the motor 8 and its output shaft I0 is adjusted by suitable mechanism or mechanisms so timed in respect to the knives I and 2 that said knives when in operating position al` ways have a component of movement in the direction of travel of the material being cut, which is substantially equal to the speed oi travel of such material. The desired length of cut is obtained by varying the speed of motor 9 and its output shaft I0 while the knives are in non-operating positions, and accordingly different lengths of cut may be obtained without injury to the material or machine. In the illustrated form of the invention the mechanism provided for the above purpose consists of a plunger I6 which is reciprocated periodically, in timed relation to the operating cycle of knives I and 2, to

adjust motor 9 to the necessary speeds. As shown this plunger I6 reciprocates in a bracket I 'I mounted on one end `of the motor, and is actuated by a rod I8 having at one end an arm I9 which is connected to plunger I6 and at its other end an arm 20 connected to a plunger 2| which slides in a bracket 22 mounted on the bed 5. The

plunger 2I is in turn moved in timed relation to the knives I and 2, by a connecting rod 28 actuated by a crank pin 24 on shaft 4. The above described timing mechanism is to be regarded merely as typical of some mechanism suitable for the purpose.

In the illustrated phase of the cycle, the knives I and 2.are in operating position and the plunger Il is disengaged from control member II, whereby the motor l may run at such speed (secured by well known methods oi regulation which need not be described in detail) which will give the knives I and 2 a component of movement in the direction of travel of the material being cut, which is substantially equal to the speed of travel of such material. As the knives move to nonoperating position, the plunger I8 will engage control member II and shift the latter to alter the speed of motor 9, and the extent to which this speed alteration takes place will determine the length of cut. Itis a simple matter to provide such an adjustment; as shown the plunger I6 is connected to the arm Il through a threaded rod 25 which may be turned by operating handle 26 to adjust the plunger Ii toward or from the control member II, and thus increase or decrease the speed variation which is imparted by motor 9 to the knives I and 2 while the latter are moving through non-operating positions. A suitable dial may be provided to indicate the length of cut for which the machine is set; as shown a worm 2'I is splined on the rod 25 and held against reciprocation by fixed collar 28. 'I'his worm 2l, however, rotates with the handle 26 and may engage a worm wheel 2l on the dial 30 cooperating with a pointer 3| which indicates the length of cut.

In instances where it is desired to coordinate the cutting speed of the knives with the speed at which the material is fed to the cut-oil' from some other machine, the motor 9 may be powered by a generator which is in turn driven in accordance with the speed at which the other machine is operated, or the motors operating both machines may be powered from the same circuit and suitable speed regulators of known character provided to conform the speed of travel of the knives while cutting, to that of the materlal.

By coordinating a motor of the above character with suitable mechanism for adjusting its speed periodically in step with the operating cycle of the knives, a high degree of precision in the length of cut may be obtained, and the complete machine becomes more simple and economical in respect to the number and cost of operating parts required, as compared to prior mechanisms for similar purposes which have involved vvariable speed transmissions, special diiferential gearings, gearings for imparting varying speeds in different phases of the cycle, etc. The machine also involves no periodic stopping or starting steps while in operation, and the variations in speed may be kept down to the minimum required for the desired length of cut under all operating conditions. The present machine also is adjustable to cut over a wide range of lengths, an important requirement in cutting corrugated paper board, and the machine may be so arranged as in the illustrated embodiment that manipulation of but one operating member is required to set it for different lengths of cut. The adjustment also may be arranged as in the illustrated embodiment so that it can be made either while the machine is running or when stationary,

this advantage of speed and facility of adjustment being also important in the cutting of corrugated paper board. For most purposes it will be convenient to set the normal speed of the motor, i. e. its speed during the operating phase of the knivesso that without any periodic speed variation the knives run continuously at the speed of travel of the material to becut for the minimum length of cut required. For cutting longer lengths, the speed of the motor will then bereduced as needed while the knives are in non-operating positions.

In ,the simple form of Vthe invention above described, it has been assumed that the feed rolls la advance the material to be operated upon at constant speed, andthat the speed of the motor during the operating period is at the time unaffected by the periodically operating speed varying mechanism. It will be understood, however, that the operation of the mechanism will be unaffected by changes in the speed of feed of the material so long as the motor is so coordinated With the feeding mechanism that the two vary together.

In the form of the invention shown in Fig. 2, the motion of the cutters is regulated by a somewhat different mechanism, including a, crank arm 32 driven by a crank pin 33 on the upper cutter shaft 3, and connected at its other end by a pin 34 to an arm 35 which rocks about a stud 35a. The arm 35 is slotted at 36 to receive a slide block 31, to which'is pivotally connected by pin 38, a rod 39, which latter is connected at its other end by pin 40 to the plunger 4|. In this instance the plunger 4i does not itself contrcl the speed of the motor but acts as a sliding guide controlling the motion of rod 39, and an arm 4|a connects plunger 4| to the armature shaft of the motor, as shown at the right of Fig. 2. Thus the spacing between the armature and field of the motor is controlled by direct mechanical connections. without the use of any spring, which is an advantage Where high speed operation is involved. The position of slide block 31 in the slot 36 may be adjusted by a screw 42 having a handle 43, so that the extent of movement of the speed regulating plunger 4| during each cycle, is controlled by the setting of slide block 31. Preferably the slot 36 is arcuate in form and concentric with the pin 4ll,` so that adjustments for different lengths of cut do not alter the position which the plunger 4| assumes during the cutting operation. The slide block 31 may be provided with a rack 44 engaging a small pinion on stud 35a the latter being provided with a suitable sprocket (not shown) for driving a chain 46 which moves the pointer 41 to indicate Von dial 48, the length of cut for any setting of slide block 31. Parts not numbered or described in Fig. 2 may be regarded as similar to those previously described in connection with Fig. 1.

While the invention has been disclosed as carried out by a machine having operating parts of certain specic constructions, it should be understood that many changes may be made therein without departing from the invention in its broader aspects within the scope of the appended claims.

I claim:

1. In combination, a cut-olf knife movable through a cycle including operatingv and non-operating positions, said knife having a component of movement in operation position which is substantially in the direction of travel of the material to be cut, a variable speed motor having an `output shaft, driving connections between said shaft'and knife for moving the latter through its cycle, a control member for regulating the speed of said motor, and means operated in timed relation to the cycle ofthe knife for periodically adjusting said control member to determine the time between successive operations of the knife and maintain its aforesaid movement during operation at substantially the same speed as the material to be cut.

2. In combination, a cut-off knife movable through. a cycle including operating and non-operating positions, said knife having a component of movement in operating position which is substantially in the direction of travel of the material to be cut, a variable speed motor having an output shaft, driving connections between said shaft and knife for moving the latter through its cycle, said motor having field and armature structures relatively axially adjustable to vary the speed of rotation of said shaft, and means operating during each cycle of said cut-off knife for adjusting the spacing of said field and armature structures of the motor to maintain the aforesaid movement of the knife during operation at substantially the same speed as the material to be cut and for altering the spacing of said structures while the knife is in non-operating position to control the length of cut.

3. In combination, a cut-off knife movablethrough a cycle including operating and non-operating positions, said knife having a component of \movement in operating position which is substantially in thedirection of travel of the material to be' cut, a motor having relatively rotatable structures one of which is connected to an output shaft, driving connections between said shaft and knife for moving the latter through its cycle,

vand means operating during each cycle of said cut-off knife for adjusting the rotary speed of the motor structure which is connected to said shaft to maintain the aforesaid movement of the knife during operation at substantially the same speed as the material to be cut; and for altering the rotary speed thereof while the knife is in nonoperating position to control the length of cut.

4. In combination, a cut-olf knife movable through a cycle including operating and non-operating positions, said knife having a component of movement in operating position which is substantially'in the direction of travel of the material to be out, a variable speed motor having an output shaft, driving connections between said shaft and knife for moving the latter through its cycle, said motor having field and armature structures relatively axially adjustable to vary the speed of rotation of said shaft, a control member connected to adjust one of said structures axially-relative to the other, means being providedv whereby said member may be adjusted to assume a substantially definite setting whenever the knife is in operating position, said means being adjustable to produce variable settings of said control member when the knife is in non-operating positions.

5. In combination, a cut-olf knife movable through a cycle including operating and non-operating positions, said knife having a component of movement in operating position which is substantially in the direction of travel of the material to be out, a variable speed motor having an output shaft, driving connections between said shaft and knife for moving the latter through its cycle, said motor having field and armature structures relatively axially adjustable to vary the speed of rotation of said shaft, a control member connected to adjust one of said structures axially relative to the other, and means periodically actuated by the knife in synchronism with the cycle of operation of the knife for shifting the position of said control member and then restoring it to its original setting, while the knife is in non-operating position.

6. In combination, an operating member movable through a cycle including operating and nonoperating positions, said member having a component of movement in operating position which is substantially in the directionof travel of the material to be operated on, a variable speed motor having an output shaft, driving connections between said shaft and member for moving the latter through its cycle, said motorv having field and armature structures relatively axially adjustable to vary the speed of rotation of said shaft, and means operated in timed relation to the cycle of said member for shifting one of said structures relative to the other to produce a variable motion of the member within its cycle.

7. In combination, an operating member movable through a cycle including operating and non-operating positions, said member having a component of movement in operating position which is substantially in the direction of travel of the material to be operated on, a variable speed motor having an output shaft, driving connections between said shaft and member for moving the latter through its cycle, said motor having eld and armature structures relatively axially adiustable to vary the speed of rotation of said shaft, and means operated in timed relation to the cycle of said member for shifting one of said structures relative to the other to produce a variable motion of the member within its cycle, said means being adjustable while the machine is running to alter the extent of such variation in movement.

8. In combination, an operating member movable through a cycle including operating and non-operating positions, said member having a component of movement in operating position which is substantially in the direction of travel of the material to be operated on, a motor having relatively rotatable structures one of which is connected to an output shaft. driving connections between said shaft and member for moving the latter through its cycle and means operated during each cycle of said member for adjusting the rotary speed of the motor structure which is connected to said shaft to impart a variation in speed of movement of the member within its cycle.

9. In combination, a cut-oil.' knife movable through a cycle including operating and nonoperating positions, said knife having a component of movement in operating position which is substantially in the direction of travel of the material to be cut, a variable speed motor having an output shaft, driving connections between said shaft and knife for moving the latter through its cycle, a control member for regulating the speed of said motor, and means operated in timed relation to the cycle of the knife for periodically adjusting said control member to determine the time between successive operations of the knife and maintain its aforesaid movement during operation at substantially the same speed as the material to be cut, said means being operable between said successive operations of the knife.

GEORGE W. SWIFI', JR. 

